title: Prevalence and features of peripheral neuropathy in Parkinson's disease patients under different therapeutic regimens.
abstract: BACKGROUND
  Recent reports suggest increased frequency of peripheral neuropathy (PN) in Parkinson's disease (PD) patients on levodopa compared with age-matched controls particularly during continuous levodopa delivery by intestinal infusion (CLDII). The aim of this study is to compare frequency, clinical features, and outcome of PN in PD patients undergoing different therapeutic regimens.
  
  
  METHODS
  Three groups of consecutive PD patients, 50 on intestinal levodopa (CLDII), 50 on oral levodopa (O-LD) and 50 on other dopaminergic treatment (ODT), were enrolled in this study to assess frequency of PN using clinical and neurophysiological parameters. A biochemical study of all PN patients was performed.
  
  
  RESULTS
  Frequency of PN of no evident cause was 28% in CLDII, 20% in O-LD, and 6% in ODT patients. Clinically, 71% of CLDII patients and all O-LD and ODT PN patients displayed a subacute sensory PN. In contrast, 29% of CLDII patients presented acute motor PN. Levodopa daily dose, vitamin B12 (VB12) and homocysteine (hcy) levels differed significantly in patients with PN compared to patients without PN.
  
  
  CONCLUSIONS
  Our findings support the relationship between levodopa and PN and confirm that an imbalance in VB12/hcy may be a key pathogenic factor. We suggest two different, possibly overlapping mechanisms of PN in patients on CDLII: axonal degeneration due to vitamin deficiency and inflammatory damage. Whether inflammatory damage is triggered by vitamin deficiency and/or by modifications in the intestinal micro-environment should be further explored. Proper vitamin supplementation may prevent peripheral damage in most cases.
authors.affiliation: Parkinson's Disease and Movement Disorders Centre, Neurology Unit, San Pio X Clinic, Fondazione Opera San Camillo, Milan, Italy. Electronic address: francesca.mancini@tin.it.
authors.forename: F
authors.initials: F
authors.lastname: Mancini
authors.affiliation: Parkinson's Disease and Movement Disorders Centre, Department of Neurology, University of Eastern Piedmont "Amedeo Avogadro", Novara, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Comi
authors.affiliation: Parkinson's Disease and Movement Disorders Centre, Department of Neurology, University of Eastern Piedmont "Amedeo Avogadro", Novara, Italy.
authors.forename: G D
authors.initials: GD
authors.lastname: Oggioni
authors.affiliation: Parkinson's Disease and Movement Disorders Centre, Neurological Institute IRCCS "C. Mondino", Pavia, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Pacchetti
authors.affiliation: Parkinson's Disease and Movement Disorders Centre, Neurology Unit, San Pio X Clinic, Fondazione Opera San Camillo, Milan, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Calandrella
authors.affiliation: Department of Neurology, Mauriziano Umberto I Hospital, Turin, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Coletti Moja
authors.affiliation: Parkinson's Disease and Movement Disorders Centre, University of Insubria, Varese, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Riboldazzi
authors.affiliation: Unit of Medical Statistics and Epidemiology, Department Translational Medicine, University of Eastern Piedmont "Amedeo Avogadro", Novara, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Tunesi
authors.affiliation: Endoscopy Unit San Pio X Clinic, Fondazione Opera San Camillo, Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Dal Fante
authors.affiliation: Parkinson's Disease and Movement Disorders Centre, Neurology Unit, San Pio X Clinic, Fondazione Opera San Camillo, Milan, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Manfredi
authors.affiliation: Parkinson's Disease and Movement Disorders Centre, Neurology Unit, San Pio X Clinic, Fondazione Opera San Camillo, Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Lacerenza
authors.affiliation: Parkinson's Disease and Movement Disorders Centre, Department of Neurology, University of Eastern Piedmont "Amedeo Avogadro", Novara, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Cantello
authors.affiliation: Department for Parkinson Disease, IRCCS San Camillo, Venice, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Antonini
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D004576:Electromyography; D005260:Female; D005492:Folic Acid / Q000097:blood; D006710:Homocysteine / Q000097:blood; D006801:Humans; D007980:Levodopa / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000097:blood / Q000150:complications* / Q000188:drug therapy; D010523:Peripheral Nervous System Diseases / Q000097:blood / Q000453:epidemiology* / Q000209:etiology*; D015995:Prevalence; D014805:Vitamin B 12 / Q000097:blood
chemical_list: D000978:Antiparkinson Agents; D006710:Homocysteine; D007980:Levodopa; D005492:Folic Acid; D014805:Vitamin B 12
keywords: Levodopa intestinal infusion; Neuropathy; Parkinson's disease